The quality result of any woodworking or woodcrafting project is entirely dependent upon the precision and skill utilized in executing that project. The slightest error in measuring, cutting, or shaping a piece may ruin the finished product, especially if there are several pieces that are supposed to be identical, but aren’t. Woodworking jigs help eliminate such mistakes, especially when a specific task is repetitive.
Jigs are not new. They’ve been in use even before the existence of power tools. They are used to hold a piece of material in place, and quite often include guides to ensure cuts or shapes are placed identically from one piece to the next. A jig may be a metal rail, a piece of scrap wood, a template, or a combination of these to allow exact replication from piece to piece.
A jig could be as simple as a stop block attached to the table surface to ensure crosscuts are all the same length down a board, without being as time consuming and error prone as measuring and marking each piece. Or they could be a board with two holes to ensure dowel holes are evenly spaced from one to the next. A more complex, but even more essential, example is a dovetail jig. If each tooth of the dovetail is not precise, it won’t fit together correctly.
Another possibility is what’s called a router jig. A lot of edges and groves would be impossible to do uniformly if they were attempted freehand. A specially shaped jig, attached to the edge or center of the piece being worked, would allow for straight lines and smooth curves that are aesthetically pleasing.
Similarly, a tenon jig can be used to ensure the depth and angle of a tenon matches the mortise into which it will seat. A tenon jig could be used with a router or a saw, and would often be attached either to the table or to the piece itself.
Basically, jigs can be inexpensive (or even free, if using scrap wood), and can provide a higher quality product in less time. Before you begin any project, think about how making jigs first can save you time and frustration.